6533b82ffe1ef96bd1294ccf

RESEARCH PRODUCT

Robust control for quantum technologies and quantum information processing

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description

We consider the robust inverse geometric optimization of arbitrary population transfers and single-qubit gates in a two-level system.Robustness with respect to pulse inhomogeneities is demonstrated.We show that for time or energy optimization, the pulse amplitude is constant, and we provide the analytic form of the detuning as Jacobi elliptic cosine.We deal with the task of robust complete population transfer on a 3-level quantum system in lambda configuration.First, we use the Lewis-Riesenfeld method to derive a family of solutions leading to an exact transfer.Among this family, we identify a tracking solution with a single parameter to control simultaneously the fidelity of the transfer, the population of the excited state, and robustness.The ultrahigh-fidelity robustness of the shaped pulses is found superior to that of Gaussian and adiabatically-optimized pulses for moderate pulse areas.Second, we apply robust inverse optimization now to generate a stimulated Raman exact passage (STIREP)considering the loss of the upper state as a characterization parameter.Control fields temporal shapes, robust against pulse inhomogeneities, that are optimal with respect to pulse area, energy, and duration, are found to form a simple sequence with a combination of intuitively (near the beginning and the end) and counter-intuitively ordered pulse pairs.Alternative robust optimal solutions featuring lower losses, larger pulse areas, and fully counter-intuitive pulse sequences are derived.